When it comes to cardiovascular health, the type of diet is less important than 'simply eating healthful foods,' researchers say.
Most people know that eating a healthful diet is crucial for keeping our heart and our cardiovascular system healthy. But which diet is best?
Researchers at Beth Israel Deaconess Medical Center (BIDMC) in Boston, MA, set out to compare the effects of three diets on heart disease risks.
Each of the three diets followed the DASH pattern while focusing on one main macronutrient: carbohydrates, proteins, or unsaturated fats.
In the carbohydrates-rich diet, around 58% of kilocalories came from carbs; the protein-rich diet replaced 10% of kilocalories from carbs with protein; and the unsaturated fat diet replaced 10% of kilocalories from carbs with unsaturated fats, for example, from avocados, nuts, and fish.
Dr. Stephen Juraschek, Ph.D., an assistant professor of medicine at BIDMC and Harvard Medical School, is the corresponding author of the study.
Dr. Juraschek and team examined the effect of the three diets on cardiovascular risk factors, such as systolic blood pressure, low density lipoprotein (LDL) cholesterol, C-reactive protein levels — a marker of inflammation — and high-sensitivity troponin, which is "a marker of subclinical cardiac injury."
The researchers published their findings in the International Journal of Cardiology.
'Simply eating healthful foods' matters most
Juraschek and team obtained their data from the so-called OmniHeart trial, a randomized intervention that followed 150 participants over 6 weeks. The average age of the participants was 54 years, 45% were women, and 55% were African American.
The researchers measured the cardiovascular risk factors at the beginning and end of each diet and compared the effects between the diets.
All three diets used the DASH dietary model, which emphasizes the consumption of vegetables, fruits, whole grains, fish, poultry, and beans.
In comparison with the baseline, the analysis revealed that all three diets had positive and prompt effects on heart health, as they all lowered the markers of inflammation and cardiac injury.
However, changing the composition of the macronutrients did not make a difference, suggesting that it does not matter whether the diet is high or low in healthful fats or carbs, but that the most important factor for improving heart injury is the general healthfulness of the diet.
"[T]hese findings suggest that a health[ful] diet, regardless of macronutrient profile, can directly mitigate subclinical cardiac damage and inflammation beyond traditional risk factors," write the researchers.
Juraschek sums up the significance of the findings, saying, "It's possible that macronutrients matter less than simply eating health[ful] foods."
"Our findings support flexibility in food selection for people attempting to eat a healthier diet and should make it easier," he continues.
"With the average American eating fewer than 2 servings of fruit and vegetables a day, the typical American diet is quite different from any of these diets, which all included at least 4 to 6 servings of fruits and vegetables a day."
"There are multiple debates about dietary carbs and fat, but the message from our data is clear: Eating a balanced diet rich in fruits and vegetables, lean meats, and high in fiber that is restricted in red meats, sugary beverages, and sweets, will not only improve cardiovascular risk factors but also reduce direct injury to the heart."
Dr. Stephen Juraschek
"Hopefully, these findings will resonate with adults as they shop in grocery stores and with health practitioners providing counsel in clinics throughout the country."